Sony Spectral Layers Pro 2

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Digital audio editing software has made amazing signal processing and manipulation possible with the click of a mouse, but until now it has been virtually impossible to take a fully mixed track and un-mix it. Sony's new Spectral Layers Pro allows you to do just that.

As Sony's training guru Gary Rebolz explains it, there's a simple analogy with a photograph. Using graphics software it's relatively simple to cut out part of a photograph and move it around before pasting it down. You can then use a clone tool to fill in the gap where the clipped portion used to be.

Precisely the same mindset applies when you're using Spectral Layers Pro: you can now select any specific part of a mixed audio clip and cut it, paste it, remove it, and alter its gain.

In the introductory video, there's a woman speaking amid a background of bird calls and wind noise. She's enjoying the forest sounds, but then an ambulance siren spoils the mood. She wishes she could get the siren to stop, but we all know that's impossible, don't we? Gary shows us how it's done, and it's the closest thing to audio magic I've ever seen!

The screen shows a graph of Frequency versus Time. This is a very different view of an audio clip and in this view, volume or amplitude is represented by brightness. Loud sounds are bright, quiet ones are subdued. The complete, mixed sound resides in a layer to the right, which is an audio equivalent of a graphic layer in Photoshop.

You now add a new layer called Siren, and select it. It turns red, meaning it is the only layer you can work on.

You choose a tool called Extract/Harmonics and simply place the pointer on the easily recognised wail of the siren. A section under the pointer turns pale blue. This is part of the fundamental frequency of the siren. If you look closer, though, you'll see that the siren sound is repeated more faintly three or four more times at equal intervals above the fundamental. These are the harmonics or overtones of the siren, and this tool automatically selects all of them. You move the tool along the siren's fundamental frequency and select as much as you want, until the entire siren sound and all of its harmonics are now contained in the Siren layer.

Now for the magic: there's a small '+' sign to the left of layer's header. This represents the phase of the audio. You click on the Siren layer's '+' sign and its phase is reversed. This means that the siren sound in the original layer and that in the Siren layer will cancel each other out. You can immediately see this in the main graph because the image of the siren sound is now missing. You can also hear the difference because all that remains is the woman's voice and the forest sounds: the siren has been completely removed.

Conclusion

This extraordinary program effectively allows you to 'paint' with sound. The possibilities are endless but include noise reduction, removal of specific musical instruments, remixing a final mix and plucking out specific sounds for use in other projects. Spectral Layers Pro integrates seamlessly with Sony Vegas (or any other NLE) and with wave programs such as Sound Forge or Audition. I am already using it professionally and will probably use it on a daily basis. I recommend you also download and use the Seminar Series of videos to help you get your head around this brilliantly original method of working with audio, although there is currently a glitch in this 1.9GB download whereby several of the clips finish too early. Hopefully Sony will fix this very soon.

Dr David Smith is a physiologist-turned-film maker. David was Associate Producer of the IMAX feature Australia Land Beyond Time and was Senior Researcher on the ABC TV series Nature of Australia. He wrote and hosted David Smith's Earthwatch on ABCTV and was 'resident zoologist' on the Don Lane and Bert Newton Shows.

In 1987 David set up his company, imaginACTION pty ltd (www.imaginaction.net.au) and has sinced written, directed and/or filmed numerous documentaries and educational multimedia projects. He has also written six books, including two Penguin eco-thrillers. Over the past five years David has moved towards medical and health-related projects, including trauma surgery, schizophrenia and emergency medicine.

David is a Fellow of the Royal Society for the Arts and a professional member of the AFI and has always been keen to share his knowledge, especially with young budding film makers. David can be contacted at david@imaginaction.net.au.